FSD IOCTLs (Windows CE 5.0)
The following table shows the file system driver (FSD) IOCTLs.
| Programming element | Description |
|---|---|
| FSCTL_GET_COMPRESSION | This IOCTL retrieves the current compression state of a file or directory on a volume whose file system supports per-stream compression. |
| FSCTL_GET_REGISTRY_INFO | This IOCTL obtains information about a registry key. |
| FSCTL_QUERY_ALLOCATED_RANGES | This IOCTL scans a file or alternate stream looking for ranges that may contain nonzero data. Only compressed or sparse files can have zeroed ranges known to the OS. For other files, the output buffer will contain only a single entry that contains the starting point and the length requested. |
| FSCTL_SET_COMPRESSION | This IOCTL sets the compression state of a file or directory on a volume whose file system supports per-file and per-directory compression. You can use this IOCTL to compress or uncompress a file or directory on such a volume. |
| FSCTL_SET_SPARSE | This IOCTL marks an indicated file as sparse. In a sparse file, large ranges of zeros may not require disk allocation. Space for nonzero data will be allocated as needed as the file is written. |
| FSCTL_SET_ZERO_DATA | This IOCTL fills a specified range of a file with zeros. |
| FSCTL_USER | This user-defined IOCTL can be used to define additional FSD IOCTLs. |
| FSSCTL_FLUSH_BUFFERS | This IOCTL flushes all buffers on a specified file system. |
See Also
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